Casting is one of those areas of filmmaking that rarely gets the glamorous publicity–you’ll never see an “Access Hollywood” feature on “Hollywood’s Hottest Cast Directors” in this or nay other lifetime–but it is arguably one of the most important aspects of the entire process. With the right actors in the parts, even fairly mediocre material can shine. On the other hand, if the wrong actors have been cast–whether they are simply no good or have been give roles that don’t properly make use of their talents–even the finest screenplays and directorial efforts will flounder. For a perfect example of a film undone by poor casting, you need look no further than “Fever Pitch,” a new romantic comedy that has a promising premise and some big laughs, but is fatally hampered by one of the most egregious casting decisions sine John Wayne chose to play Genghis Khan in “The Conqueror”–Jimmy Fallon, a performer whose work on “Saturday Night Live” and the woeful “Taxi” has been so lazy that he makes Norm McDonald commitment to his craft seem positively Stanislavskian by comparison, as a sympathetic romantic lead whom we are supposed to care about. Because he can’t be bothered to give such a performance (or any other, for that matter), it is impossible to care about what happens to him and as a result, the film, despite some bright spots, never quite works.

Opening in the winter of 2003, the film starts as Ben (Fallon) and Lindsey (Drew Barrymore) meet cute and fall in love, as the kids today so often do. Everything seems to be going swimmingly until spring rolls around and Ben finally gets around to confessing his dark secret–he is a Boston Red Sox fanatic, a fact which he admits has caused some friction in his previous relationships. Surprisingly, Lindsey is okay with this–she doesn’t want to be the kind of girlfriend who makes her lover change his entire life in order to please her and she also likes that he can feel genuine passion and excitement for an outside interest. What she doesn’t realize is that he is really a Red Sox fanatic–the kind who heads down to Florida for spring training, covers his ears his ears in public to avoid hearing the score of a game he is taping and owns a closet containing 50 Sox jerseys and one pair of shoes.

Finally, after he puts the team above everything else one time too many–he turns down a weekend trip to France to catch the series against the Mariners (“When your girlfriend invites you to go to Paris for the weekend, you say ‘Yes’!”)–he tries to put Lindsey above his beloved team. Unfortunately for him, the very game that he decides to completely blow off–not even videotaping–turns out to be the crucial game that fueled the team’s improbable drive to the playoffs. When he freaks over having missed “the greatest game ever,” they split up and a despondent Jimmy holes up in his apartment eating chicken wings and rewatching a video of Bill Buckner’s 1986 bumble that helped cost the Red Sox the World Series. Finally, he decides to make the ultimate sacrifice–selling off his prized season tickets (“Ted Williams would roll over in his freezer!”) to prove his love. When Lindsey hears about this, she rushes to the park to try to stop him. Does she succeed? All I will say is that her chances of stopping him are about as slim as the Red Sox’s are of making it to the World Series, and we all know how that turned out, don’t we?

With its basic story of a grown man slowly being prodded from his arrested adolescence and devotion to pop-culture ephemera by the love of a far more sensible woman, “Fever Pitch” may remind some of you of such recent films as “High Fidelity” and “About a Boy”–this is not really a coincidence as all three come from books by British author Nick Hornby. While the previous translations stuck fairly close to Hornby’s original (although “High Fidelity” changes its locale from London to Chicago), “Fever Pitch” has undergone many changes for this American version. The original book found Hornby writing about his devotion to a soccer team–since no one in the States cares about soccer, the focus was changed to a baseball team that, at one point, was second only to the Chicago Cubs for its ability to snatch defeat from the jaws of victory. Additionally, as the film has been directed by Peter and Bobby Farrelly, still best known for “There’s Something About Mary,” room has been made for their trademarks as well, such as bit parts being filled by family friends and handicapped people and a few bits of gross-out humor, such as a first date that is derailed when Lindsey is struck with food poisoning. (If you are curious, there is a more faithful adaptation of the book, filmed in England and starring Colin Firth, that is currently available on DVD.)

Although the translation is relatively smooth, there are a couple of bumps. The gross stuff seems even more unnecessary than usual and seems to have been thrown in so as not to scare the Farrelly core audience away with all the mushy stuff. And as we all know, the Red Sox pulled off one of the greatest World Series victories of all time last year, which necessitated a lot of last-minute rewrites. Unfortunately, this winds up subverting two of the film’s key scenes; when Ben wails about missing “the greatest game ever,” his obsession doesn’t seem too off-base because it actually was a stunning turnaround. As for the finale, in which Ben is about to sign over his tickets at what appears to be the final moments of the last playoff game after the Yankees, his apparent disinterest towards the game unfolding doesn’t quite make the sense that it might have if it had been just another meaningless game.

These are minor quibbles and are easily overcome by the film’s virtues. “Fever Pitch” contains two things that I always like seeing in a comedy, especially one of the romantic variety. One is the sight of a character who is thoroughly enmeshed by a particular obsession and is helpless in its thrall even when he knows what it is doing to him. It is funny, for example to hear Ben and his Fenway cohorts discuss the sad history of Red Sox flameouts (“Bucky Frickin Dent!”) or to see Lindsey get a glimpse of his apartment and remark “It’s like you live in a gift shop.” The other is Drew Barrymore, who is one of those performers who is just so cheerful and good-natured that her mere presence can brighten up almost any film that she graces, with the exception of “Charlie’s Angels: Full Throttle.” As Lindsey, she is so full of sweetness and life that you can believe how she might inspire a baseball fanatic to forsake his favorite team for someone who once publicly remarked “It’s just a game.” (I also appreciated the presence by Ione Skye, the heartbreaker from “Say Anything” making a welcome comeback in a brief role that left me wanting more.)

What I can’t believe, and this is the point upon which the whole movie eventually flounders, is that she would even give the time of day to someone like Jimmy Fallon–in a career that has seen her as the better half in celluloid relationships involving the likes of Adam Sandler, Tom Green and E.T., this is by far the least convincing on-screen coupling of her career. Don’t blame her, the fault is all Fallon’s because he doesn’t seem to realize that the lone performing style that he developed on “SNL”–one that resembles the class cut-up who hasn’t done any of his homework and who is trying to bluff his way through class on charm alone–may work in very short doses in 5-minute TV sketches, it gets pretty excruciating when stretched out to the length of a feature. This is bad enough during the flat-out comedic moments but the worst parts of “Fever Pitch” are the ones where he tries and utterly fails to be charming and romantic–his declarations of love are so far removed from genuine emotion that it feels as if he is waiting for a laugh track after every line. This may be the first romantic comedy where the hero pitches woo and balks.